The present invention relates to circuits for processing a useful signal which varies in amplitude between positive and negative values about a zero value and contains information in the locations of its zero passages.
During the transmission of digital signals over a transmission path, e.g. record disc, magnetic tape or wire, signal distortions generally occur. It is therefore necessary to process such a signal before evaluation. For digital signals, it is usually important, in this connection, to reconstruct the zero passages of the originally transmitted signal as accurately as possible.